This invention relates to a pushbutton switch device. More particularly, this invention relates to a pushbutton switch device having a flat carrier on which the switch contacts are placed and having a switch button arrangement with several elastic switch buttons, each elastic switch button designed for actuation of a corresponding first and second switch contacts, in which one actuation of the elastic switch button closes two switch contacts, each switch contact consisting of one contact pair and each switch contact being electrically independent of one another, with the stroke of the switch button needed to actuate the first switch contact being greater than the stroke needed for actuation of the second switch contact.
A pushbutton switch device of this kind is described in West German Patent Publication No. DE-OS 30 41 859. There, a pushbutton switch is disclosed where formed onto the flat carrier are switch chambers in which two switch contacts are placed one on top of another. The associated switch button has an elastic rubber switch knob for closing the contacts. When the switch knob is actuated, first the upper switch contact and then the lower switch contact is closed since the switch contacts are placed one above the other. The configuration of the switch knob contributes nothing to the successive switching of the switch contacts, so that the successive switching process depends only on the spacing between the switch contacts or the thickness of the spacer foil separating them. One drawback to such a design is that since the thickness of the spacer foil is small, it is possible for switching to occur practically simultaneously. In addition, the carrier plate must be designed so that the foil carrying the upper switch contact can be deformed since otherwise switching of the lower switch contact would be impossible.
West German Patent Publication No. DE-OS 29 02 769 discloses a similar pushbutton switch device. In this case, only short switching strokes can be executed.